v1.6, 20041026, ht
THURSDAY, OCTOBER 28
T1 PHYSICS OF SOUND AND HEARING
Presenter: J.J. Johnston, Microsoft
Abstract:
In this tutorial, we will present some basic acoustic and psychoacoustic issues and phenomenon, and relate them to the practice of digital audio. In the process, we will discuss:
Low SPL's and how they relate to the noise at the eardrum.
High SPL's and the nonlinearity of atmospheric transmission.
Low and High frequencies, and how they propagate.
How one ear hears, outer, middle, and inner ears, and the cochlear filters.
What is masking and why do I care about it?
How Binaural hearing, HRTF's and soundfields interact.
Why is SNR "Mostly useless"?
Thursday, October 28, 9:00 am – 11:00 am
T2 SUBJECTIVE MICROPHONE COMPARISONS
Presenter: Jürgen Wahl, Sennheiser/Neumann, USA
Abstract:
The purpose of this workshop is to analyze the variables that make it so difficult to predict a microphone’s performance in actual applications, and to understand why microphones with seemingly identical technical specifications sound differently, even when used under the same circumstances. The tutorial will demonstrate how to concentrate on less complex segments of performance behavior. For example, when evaluating electronic performance, we can concentrate on good signal-to-noise ratio, low self-noise during very quite passages, and minimal distortion components in the non-linear operating range. To evaluate the microphone’s acoustic behavior we listen for the imaging of instruments, how it captures room acoustic, reverberation, ambience, and distant instruments. When we analyze the tonal characteristic of the microphone under test, we may include the natural frequency response for all instruments, the extended frequency range, the transient response, the uniform polar pattern, the detailed resolution of harmonic components, and how the microphone works together with other microphones.
Thursday, October 28, 1:30 pm – 3:30 pm
T3 ACOUSTICS -1
Presenter: Anthony Grimani, Performance Media Industries, Ltd
Abstract:
The acoustical properties of a room highly influence the perceived sonic quality of any monitoring system. Tutorials T3 and T5 will focus on applications for small room acoustics, such as recording studios, project studios, listening rooms, screening rooms, home theaters. The information will cover all the details that affect acoustics and will provide simple recipes for improving quality and consistency. Basic knowledge of audio theory, wave theory and acoustics are recommended. This is the first of two acoustics tutorials, and covers topics such as: Sound Isolation through decoupling, mass, and damping, Background noise control, Vibration and rattle control.
Thursday, October 28, 1:30 pm – 3:30 pm
T4 AUDIO POST PRODUCTION
Presenter: Tomlinson Holman, USC Cinema-Television and TMH Corporation
Abstract:
Audio produced for accompanying pictures has some specialized considerations that don't appear elsewhere in the field, and this tutorial will emphasize these topics. Among them are audio/video synchronization, dialogue and sound effects editing and mixing, and specialized forms of tools used elsewhere in audio such as equalization, noise reduction, and so forth. Also, multichannel sound is the norm here, and since the sound accompanies a picture, issues of picture/sound spatial matching apply. Another factor is the multiple stages of the workflow needed to tame the potentially hundreds of tracks in use.
Thursday, October 28, 4:00 pm – 6:00 pm
T5 ACOUSTICS -2
Presenter: Anthony Grimani, Performance Media Industries, Ltd
Abstract:
The acoustical properties of a room highly influence the perceived sonic quality of any monitoring system. Tutorials T3 and T5 will focus on applications for small room acoustics, such as recording studios, project studios, listening rooms, screening rooms, home theaters. The information will cover all the details that affect acoustics and will provide simple recipes for improving quality and consistency. Basic knowledge of audio theory, wave theory and acoustics are recommended. This is the second of two acoustics tutorials, and covers topics such as: Room dimensioning for optimized bass resonance, Acoustical treatments for optimized reflections, echoes, and decay time. These include resistive absorbers, Helmholtz resonator absorbers, tympanic and pistonic resonator absorbers, and various forms of diffusers.
Thursday, October 28, 6:00 pm – 8:30 pm
T6 LIVE ORGAN CONCERT RECORDING
Presenter: Ron Streicher, Pacific Audio-Visual Enterprises, Pasadena, CA, USA
Abstract:
The tutorial will center on the setup and recording of Graham Blyth's Organ Concert at Grace Cathedral. This will be a "hands-on" session, with direct involvement of any and all who attend. Participants should come prepared to work. We will do everything required to setup and record this concert, from unloading the van of equipment through to reloading following the concert. All aspects of this process will be thoroughly discussed during the setup process:
- microphone selection and placement
- microphone stand security and safety
- cable routing and taping for safety
- equipment configuration: the recording chain
- choice of recording formats for stereo and surround
- ProTools session setup for stereo and surround
- multi-track (DA78HR) equipment setup
- the "on-location monitoring dilemma" (i.e. headphones or loudspeakers)
- techniques for logging the session (i.e. the "paperwork")
- striking the session: cable coiling the RIGHT WAY
| FRIDAY, OCTOBER 29 |
T7 THE BASICS OF DIGITAL AUDIO: A Seminar with Demonstrations
Presenters:
Stanley Lipshitz & John Vanderkooy, Audio Research Group, University of Waterloo, Canada
Abstract:
This is an introductory-level seminar aiming to explain and demonstrate with "live" examples the two fundamental aspects of any digital audio system -- sampling and quantization. These two operations will be discussed and illustrated in real-time using a custom-built sampler and quantizer. This will enable us to present some of the pathologies of such systems, which should not normally be audible, and also show that, when properly implemented, a digital system has analog characteristics. This will make the presentation interesting to newcomers and "old pros" alike.
Topics to be covered will include:
-- sampling only (without quantization)
-- sampling artifacts (aliases & images)
-- reconstruction
-- quantization only (without sampling)
-- quantization errors
-- dither
The demonstrations will enable the audience to hear and see what is going on, both good and bad.
Friday, October 29, 9:00 am – 11:00 am
T8 MICROPHONE TECHNIQUES FOR MUSIC
Presenter: Bruce Bartlett, Crown International
Abstract:
This presentation covers the theory and practice of microphone techniques for music recording (mic choice and placement). The first half of the presentation explains microphone transducer types, frequency response, polar patterns, and the advantages of each. Some basic guidelines are presented that apply to all mic techniques. The second half describes several microphone techniques in common use for specific instruments and vocals. Both multi-miking and stereo miking are covered.
Friday, October 29, 11:30 am – 1:30 pm
T9 ALL ABOUT LOOPING AND TIME-STRETCH TECHNOLOGIES
Presenter: Craig Anderton, EQ Magazine
Abstract:
The ability to change the pitch and timing of digital audio is essential for various types of music, particularly modern electronic and dance music. Several technologies have been applied to this problem, but as yet, there is no "one size fits all" solution. This tutorial explains the different technologies, which are best suited to which applications, how to optimize stretching technologies, workarounds for existing problems, and how these technologies are applied in musical contexts. Extensive usage of real world audio examples expand on and illustrate the concepts presented in this tutorial.
Friday, October 29, 11:30 am – 1:30 pm
T10 CENTER CHANNEL CHALLENGE
Presenter: Jeff Levison, DTS Entertainment
Abstract:
The center channel has long been the audio image anchor for the cinema but has found difficulty fitting into easy use for multichannel music. This tutorial will examine a variety of mixing techniques for the center channel and its incorporation in popular music by evaluating artistic stereo goals and translating them into multichannel.
Friday, October 29, 2:00 pm – 4:00 pm
T11 DIGITAL PLUMBING FOR STUDIO, BROADCAST AND LIVE AUDIO
Presenter: Michael Poimboeuf, Digidesign
Abstract:
This seminar presents an overview of commonly used digital audio interconnection technologies, including cabling, circuits, modulation theory, and analysis techniques for performance measures. The interconnect technologies we study include AES-3 (AES/EBU), IEC60958 (S/PDIF), and IEEE802.3 (ethernet). Cabling includes shielded 110ohm twisted pair, UTP and ScTP “category” cable (Cat5/5e/6), and 75ohm coaxial cable. Circuits include clock/data recovery and PLLs. Analysis techniques and performance measures range from eye-diagrams, and transport jitter measurements, to bit error rate (BER) estimation based on signal-to-noise measures such as NEXT, FEXT, and Alien Crosstalk. We conclude with discussion of new interconnection technology currently in development.
Friday, October 29, 2:00 pm – 4:00 pm
T12 DESIGN AND USE OF MICROPHONE PREAMPLIFIERS
Presenter: John LaGrou, Millennia Music & Media Systems
Abstract:
Microphone Preamplifiers are one of the few essential analog functions in an increasingly digital audio world. In this tutorial, we will discuss mic preamp application and technology. Can we have too many mic preamps in our studio? Attend this tutorial and find out.
Friday, October 29, 4:30 pm – 6:30 pm
T13 PLANNING FOR SUCCESS IN LIVE SOUND REINFORCEMENT:
Practical Considerations for Performance Audio
Presenters: David Scheirman, JBL Professional, , with Dave Shadoan, "Dr. Don" Pearson, and Robert Scovill
Abstract:
Of interest to students, working system operators, and audio system/product designers alike, this tutorial presents an overview of the challenges faced by sound system technicians and operators who must deal with complex interactions between performers, audiences, acoustical spaces and environmental challenges. Topics include how to plan in advance for successful system deployments, understanding gain stages and the signal path from microphone to loudspeaker, and various decision paths taken by practitioners who balance audio engineering theory with practical applications in the field. Various tips and tricks related to stage plots, input lists, mixing console configurations and speaker array formats will highlight the session. This tutorial will investigate these issues in depth, drawing upon the combined experiences of several working live sound professionals including a high-profile independent concert sound mixer, a leading rental sound company owner, and a noted system engineer.
Friday, October 29, 4:30 pm – 6:30 pm
T14 DESIGNING WITH DELTA-SIGMA CONVERTERS
Presenter: Steve Green, Cirrus Logic, Inc. / Crystal Semiconductor
Abstract:
The performance of integrated Analog-to-Digital and Digital-to-Analog converters integrated circuits continue to improve as new techniques and processes become available to the IC design engineer. Many subtleties must be understood and addressed in order to realize optimal performance of these devices.
| SATURDAY, OCTOBER 30 |
T15 AUDIO TESTING ACCORDING TO AES-17, A GUIDED TOUR TO IMPLEMENTING THE STANDARD
Presenter: Richard Cabot, Qualis Test Systems
Abstract:
The AES digital audio measurement standard has existed for more than a decade and is accepted as the definitive document when assessing the performance of professional digital audio equipment. This tutorial will cover the various performance parameters and the measurements used to quantify them. Their origin, the rationale behind their use and the limitations of their application will be discussed. Each implementation of each measurement in the standard will be diagrammed in terms of the equipment required for implementation. Where several implementation approaches are possible the advantages and disadvantages of each will be considered.
Saturday, October 30, 9:00 am – 11:00 am
T16 SURROUND SOUND FOR PICTURE, DRAMATURGICAL GOALS - TOOLS AND CONCEPTS
Presenter: Florian Camerer, ORF - Austrian TV
Abstract:
5.1 Surround Sound is primarily established as a means to heighten the experience of the recipient of a combined audio-visual event, mainly in the movie world and in its wake the success of the DVD in home theaters. There exists a set of dramaturgical tools for raising the listening/viewing experience through proper use of the additional channels. Nevertheless many concepts are exclusively based on long-term work-experience of "what works and what doesn’t work". In this tutorial several surround-sound- design-concepts are traced down to more deeper psychological roots, new terms are introduced as well as advanced solutions going beyond what is possible (dramaturgically) in the cinema world are presented. The main body of examples of the author come from the TV-documentary area - one of the mixes will even be dismantled into the different stem mixes to illustrate the process of sound-track-crafting with special focus on surround sound.
Saturday, October 30, 11:30 am – 1:30 pm
T17 GROUNDING AND SHIELDING
Presenter: Bill Whitlock, Jensen Transformers, Inc.
Abstract:
Many designers and installers of audio/video systems think of grounding and interfacing as a “black art.” Do signal cables really “pick up” noise, presumably from the air like a radio receiver? Equipment manufacturers, installers, and users rarely understand the real sources of system noise and ground loop problems, routinely overlooking or ignoring basic laws of physics. Although myth and misinformation are epidemic, this tutorial brings insight and knowledge to the subject.
Signals accumulate noise and interference as they flow through system equipment and cables. Both balanced and unbalanced interfaces transport signals but are also vulnerable to coupling of interference from the power line and other sources. The realities of ac power distribution and safety are such that some widely used noise reduction strategies are both illegal and dangerous. Properly wired, fully code-compliant systems always exhibit small but significant residual voltages between pieces of equipment as well as tiny leakage currents that flow in signal cables. The unbalanced interface has an intrinsic problem, common-impedance coupling, making it very vulnerable to noise problems. The balanced interface, because of a property called common-mode rejection, can theoretically nullify noise problems. Balanced interfaces are widely misunderstood and their common-mode rejections suffer severe degradation in most real-world systems. Many pieces of equipment, because of an innocent design error, have a built-in noise coupling mechanism dubbed the “pin 1 problem” by Neil Muncy. A simple troubleshooting method that uses no test equipment will be described. It can pinpoint the exact location and cause of system noise. Most often, devices known as ground isolators are the best way to eliminate noise coupling. Signal quality and other practical issues are discussed as well as how to properly connect unbalanced and balanced interfaces to each other. While immunity to RF interference is a part of good equipment design, it must often be provided externally. Finally, power line treatments such as technical power, balanced power, power isolation transformers, and surge suppression are discussed.
Saturday, October 30, 11:30 am – 1:30 pm
T18 DYNAMIC RANGE COMPRESSION
Presenters: David Berners & Jonathan Abel, Universal Audio & CCRMA Stanford University
Abstract:
This tutorial section covers automatic gain control (AGC), with applications including dynamic range compressors, limiters, gates, and companders. Topics include signal level detection techniques, gain control topologies, and DSP modeling techniques. Parameters such as attack, release, and ratio will be discussed in relation to perceptual color and application. Properties of various technologies including opto-, FET-, and VCA- based compression will be covered, also in relation to desired behavior for various applications. Program dependence, lookahead, and sidechaining will also be discussed. Time permitting, the tutorial will cover de-essing, multichannel compression, and multiband compression.
Saturday, October 30, 2:00 pm – 4:00 pm
T19 ANALOG DESIGN IN A DIGITAL ENVIRONMENT
Presenters: Dennis Bohn, Rick Jeffs, Paul Mathews, Rane Corporation
Abstract:
This tutorial presents a fast-paced overview of the problems faced by an analog audio designer working in the mixed analog-digital environment found in most pro audio products. A typical mixed analog-digital audio product is examined with respect to the analog design elements necessary to maintain pristine audio performance while satisfying international EMC and safety compliance. Topics include how to bring in low-level signals, maintain fidelity and SNR, provide high gain and buffering, supply clean power, and deliver high quality signals on the output side, all within the context of a hostile environment both inside and outside the product housing. Examples of gotchas and do’s and don’ts in chassis design, circuit design, and circuit board layout highlight the session.
Saturday, October 30, 2:00 pm – 4:00 pm
T20 REVERBERATION ACOUSTICS, ANALYSIS AND SYNTHESIS
Presenters: Jonathan Abel & David Berners, Universal Audio & CCRMA Stanford University
Abstract:
This tutorial presents a review of reverberation analysis and synthesis methods, along with a discussion of reverberation acoustics and psychoacoustics. Although the details of reverberated sound are extremely sensitive to environment and geometry particulars, human listeners appear to pay attention only to certain statistical features, such as decay rate as a function of frequency. In this tutorial, we explore these features and their physical origins, and present signal processing structures to synthesize them. The psychoacoustics of early reflections and the late-field envelope are reviewed. Artificial reverberators based on convolution and on feedback delay networks and which synthesize desired early reflection and late-field features, are described.
Saturday, October 30, 4:30 pm – 6:30 pm
T21 DSP -1: ARCHITECTURES AND HARDWARE
Presenter: Dennis Fink, Mathematical Systems Design & Universal Audio
Abstract:
DAWs, rack mount signal processors, DSP cards, and effects pedals tend to use DSP chips, microprocessors or microcontrollers as their engines. In this tutorial, we'll look at and compare system architectures for these products and the hardware devices used to implement them. We'll focus on the common attributes of DSP chips required by audio algorithms and the transport of digital signals in and out of the chip. A brief comparison of commercially available DSP chips and an historical timeline of DSP hardware will be presented as well. This is a detailed overview for those of us not actively working as digital audio hardware engineers.
Saturday, October 30, 4:30 pm – 6:30 pm
T22 MASTERING FOR STEREO AND SURROUND
Presenter: Bob Ludwig, Gateway Mastering
Abstract:
Bob will present a Tutorial on Stereo and Surround Sound mastering. Mastering remains a somewhat misunderstood topic. For all the press on the recording process there are only few good books available that discuss the mastering process. Mastering is the final creative step in the record making chain, it determines how the final CD or DVD will sound. Then it becomes the first step in the manufacturing chain, creating the production master from which all the replicated discs will be made. Bob will discuss many aspects of mastering with emphasis on the fact that mastering is not just making an original recording louder. There are many creative decisions that need to be made. He will focus on a few specific titles he has worked on and cover what was involved in their mastering.
| SUNDAY, OCTOBER 31 |
T23 SYNCHRONIZATION
Presenter: Fred Katz, Omega Recording Studios
Abstract:
Perhaps no subject in audio engineering is more misunderstood by students and working professionals alike than synchronization. Its principles are derived from seemingly unrelated fields like television and video production, the math involved is unwieldy and often counterintuitive, and when is applied successfully its results are transparent and easily overlooked. Yet the topic of synchronization is relevant to almost every type of recording project, especially those involving digital audio, video or multimedia, and MIDI and sampling. This presentation will attempt to clarify the fundamental principles of synchronization and will show how they can be applied by examining several common synchronization scenarios involving analog, digital, and video tape, MIDI, Pro Tools, and digital audio networks.
Sunday, October 31, 11:30 am – 1:30 pm
T24 DSP -2: ALGORITHMS AND SOFTWARE
Presenter: Dennis Fink, Mathematical Systems Design & Universal Audio
Abstract:
Digital equalizers, mixers, crossovers, and limiters found in plug-ins or hardware all use variants of a common set of algorithms. This tutorial looks at these audio processes and the time and frequency domain algorithms used to implement them. We'll talk about analog versus digital processing, algorithm times, sample- versus buffer- processing, DSP utilization, and parameter control. We'll look at high level and assembly language programming and consider the 5 major algorithm classes: IIR filters, FIR filters, interpolator/decimators, modulators, and FFTs. This is a detailed overview of what audio DSP algorithm designers and programmers do.
Sunday, October 31, 11:30 am – 1:30 pm
T25 ACOUSTIC ISSUES CONCERNING SMALL STUDIO ENVIRONMENTS
Presenter: John Storyk, Walters-Storyk Design Group
Abstract:
Contrary to many beliefs, small studio environments present a special breed of acoustic issues, some in common but many unique to the small size of both recording and listening rooms.
This tutorial will investigate many of these issues, including: low frequency control, speaker placement, ergonomic design, including listening positioning, furniture design and other object effects on room acoustic response, currently available design, prediction and measuring tools – including demonstrations of some of these applications, real world experiences, including pictures and diagrams of many “small studio” environments, tips and tricks.
